Heat exchanger and air conditioner

ABSTRACT

A plurality of flat tubes is, at one end thereof, connected to a first header collecting pipe, and is, at the other end thereof, connected to a second header collecting pipe. Some of the flat tubes forms a main heat exchange part, and the other flat tubes forms an auxiliary heat exchange part. The number of flat tubes of the auxiliary heat exchange part is less than the number of flat tubes of the main heat exchange part. The total cross-sectional area of flow paths per flat tube provided in the auxiliary heat exchange part is greater than the total cross-sectional area of flow paths per flat tube provided in the main heat exchange part.

TECHNICAL FIELD

The present disclosure relates to a heat exchanger including flat tubesand fins and configured to exchange heat between fluid flowing throughthe flat tube and air, and to an air conditioner.

BACKGROUND ART

Conventionally, a refrigerating apparatus has been known, which iscapable of performing a refrigeration cycle by refrigerant circulatingthrough a refrigerant circuit and performing an operation for cooling atarget object (e.g., air or water) with refrigerant and an operation forheating the target object with refrigerant. For example, Patent Document1 discloses an air conditioner including the refrigerating apparatus ofthis type. In the air conditioner during an air-cooling operation forcooling indoor air, an outdoor heat exchanger functions as a condenser,and an indoor heat exchanger functions as an evaporator. On the otherhand, in the air conditioner during an air-heating operation for heatingindoor air, the indoor heat exchanger functions as the condenser, andthe outdoor heat exchanger functions as the evaporator.

Patent Document 2 also discloses an air conditioner configured toperform a refrigeration cycle. In a refrigerant circuit of the airconditioner, an outdoor heat exchanger configured to exchange heatbetween refrigerant and outdoor air is provided. The outdoor heatexchanger is a heat exchanger including two headers each formed in acylindrical shape, and a plurality of flat heat transfer pipes providedbetween the headers.

Moreover, Patent Document 3 also discloses a heat exchanger includingheaders and flat heat transfer pipes. The heat exchanger disclosed inPatent Document 3 functions as a condenser. In the heat exchanger, amain heat exchange part for condensation and an auxiliary heat exchangepart for sub-cooling are formed. While passing through the main heatexchange part, refrigerant flowing into the heat exchanger is condensedinto a substantially liquid single-phase state. Then, the refrigerantflows into the auxiliary heat exchange part, and is further cooled.

CITATION LIST Patent Document

PATENT DOCUMENT 1: Japanese Patent Publication No. 2008-064447

PATENT DOCUMENT 2: Japanese Patent Publication No. H09-014698

PATENT DOCUMENT 3: Japanese Patent Publication No. 2010-025447

SUMMARY OF THE INVENTION Technical Problem

However, in the case where the main heat exchange part for condensationand the auxiliary heat exchange part for sub-cooling are formed in theheat exchanger including the headers and the flat heat transfer pipes(flat tubes), the auxiliary heat exchange part typically has flow pathsfewer than those of the main heat exchange part. Thus, there is apossibility that a flow velocity in the auxiliary heat exchange partincreases, and therefore a pressure loss in the auxiliary heat exchangepart increases.

The present disclosure has been made in view of the foregoing, and it isan objective of the present disclosure to reduce, in a heat exchanger inwhich headers and flat tubes are provided and a main heat exchangepart(s) for condensation and an auxiliary heat exchange part(s) forsub-cooling are formed, a pressure loss in the auxiliary heat exchangepart.

Solution to the Problem

In order to solve the foregoing problem, a first aspect of the inventionis intended for a heat exchanger including a plurality of flat tubes(53, 58) arranged in the vertical direction such that side surfacesthereof face each other and each formed with a plurality of flow paths(49) of fluid, and a plurality of fins (54, 59) configured to dividepart between adjacent ones of the flat tubes (53, 58) into a pluralityof air passages through each of which air flows. The heat exchangerincludes a first header collecting pipe (51, 56); and a second headercollecting pipe (52, 57). Each flat tube (53, 58) is, at one endthereof, connected to the first header collecting pipe (51, 56), and is,at the other end thereof; connected to the second header collecting pipe(52, 57). Some of the flat tubes (53) form a main heat exchange part(50), and the other flat tubes (58) form an auxiliary heat exchange part(55). The flat tubes (58) forming the auxiliary heat exchange part (55)are fewer than the flat tubes (53) forming the main heat exchange part(50). The total cross-sectional area of flow paths (49) per flat tube(58) in the auxiliary heat exchange part (55) is greater than the totalcross-sectional area of flow paths (49) per flat tube (53) in the mainheat exchange part (50). If the heat exchanger serves as a condenser,refrigerant is condensed in the main heat exchange part (50), and therefrigerant is sub-cooled in the auxiliary heat exchange part (55).

In the foregoing configuration, the number of flat tubes (58) formingthe auxiliary heat exchange part (55) is less than the number of flattubes (53) forming the main heat exchange part (50). However, the totalcross-sectional area of flow paths (49) per flat tube (58) in theauxiliary heat exchange part (55) is greater than the totalcross-sectional area of flow paths (49) per flat tube (53) in the mainheat exchange part (50). Thus, if the heat exchanger serves as thecondenser, the flow velocity of refrigerant in the auxiliary heatexchange part (55) can be lowered as compared to a heat exchanger inwhich a single type of flat tubes forms a main heat exchange part and anauxiliary heat exchange part.

A second aspect of the invention is intended for the heat exchanger ofthe first aspect of the invention, in which the width (W2) of each flattube (58) of the auxiliary heat exchange part (55) is greater than thewidth (W1) of each flat tube (53) of the main heat exchange part (50),and the flow paths per flat tube (58) in the auxiliary heat exchangepart (55) is more than the flow paths per flat tube (53) in the mainheat exchange part (50).

In the foregoing configuration, the number of flow paths per flat tube(53, 58) and the width (W1, W2) of the flat tube (53, 58) are adjustedto set the total cross-sectional area of flow paths (49) per flat tube(53, 58).

A third aspect of the invention is intended for the heat exchanger ofthe first or second aspect of the invention, in which each flow path(49) is formed with a plurality of grooves in a corresponding one of theflat tubes (53) of the main heat exchange part (50), and each flat tube(58) of the auxiliary heat exchange part (55) is a bare pipe.

In the foregoing configuration, since the grooves (49 a) are formed inthe flat tube (53) for the main heat exchange part (50), the surfacearea per refrigerant flow path (49) can be increased.

A fourth aspect of the invention is intended for the heat exchanger ofany one of the first to third aspects of the invention, in which eachfin (236) is formed in such a plate shape that a plurality of cut parts(245) into each of which a corresponding one of the flat tubes (53, 58)is inserted are provided, the fins (236) are arranged at predeterminedintervals in an extension direction of the flat tubes (53, 58), eachflat tube (53, 58) is sandwiched between peripheral edge parts of acorresponding one of the cut parts (245) of the fins (236), and, in eachfin (236), part between adjacent ones of the cut parts (245) arranged inthe vertical direction forms a heat transfer part (237).

In the foregoing configuration, the plurality of fins (236) each formedin a plate shape are arranged at the predetermined intervals in theextension direction of the flat tubes (53, 58). In each fin (236), theplurality of cut parts (245) into each of which a corresponding one ofthe flat tubes (53, 58) is inserted are formed. The flat tube (53, 58)is sandwiched between the peripheral edge parts of a corresponding oneof the cut parts (245) of the fin (236). Moreover, in the fin (236), thepart between adjacent ones of the cut parts (245) arranged in thevertical direction forms the heat transfer part (237).

A fifth aspect of the invention is intended for the heat exchanger ofthe fourth aspect of the invention, in which an end of each flat tube(53, 58) in a width direction thereof is aligned with an end of acorresponding one of the cut parts (245) on an open side thereof.

In the foregoing configuration, the end of the flat tube (53, 58) in thewidth direction thereof is aligned with the end of the cut part (245) onthe inlet side thereof. Thus, when a brazing material for joining thefin (236) and the flat tube (53, 58) together is applied, the brazingmaterial can be easily set on a side close to the cut part (245).

A sixth aspect of the invention is intended for an air conditionerincluding a refrigerant circuit (20) provided with the heat exchanger(40) of any one of claims 1-5. Refrigerant circulates to perform arefrigeration cycle in the refrigerant circuit (20).

In the foregoing configuration, the heat exchanger is connected to therefrigerant circuit (20). In the heat exchanger, refrigerant circulatingthrough the refrigerant circuit (20) flows through the flow paths (49)of the flat tubes (53, 58) to exchange heat with air flowing through airpassages.

Advantages of the Invention

According to the first aspect of the invention, if the heat exchangerserves as the condenser, the flow velocity of refrigerant in theauxiliary heat exchange part (55) can be lowered, and therefore apressure loss in the auxiliary heat exchange part (55) can be reduced.

According to the second aspect of the invention, the totalcross-sectional area of flow paths (49) in the flat tube (53) for themain heat exchange part (50) and the total cross-sectional area of flowpaths (49) in the flat tube (58) for the auxiliary heat exchange part(55) can be easily set. For example, even if the flow paths (49) for themain heat exchange part (50) and the auxiliary heat exchange part (55)are different from each other in shape, and it is difficult to identifythe difference in shape of the flow path (49) with eyes, the flat tube(53) for the main heat exchange part (50) and the flat tube (58) for theauxiliary heat exchange part (55) are different from each other in width(W1, W2), and therefore both pipes (53, 58) can be easily identifiedwith eyes.

According to the third aspect of the invention, in the flat tube (53)for the main heat exchange part (50), a heat exchange efficiency in themain heat exchange part (50) can be improved. Moreover, in the flat tube(58) for the auxiliary heat exchange part (55), a pressure loss due to apipe shape can be further reduced.

According to the fifth aspect of the invention, the brazing material forjoining the fin (236) and the flat tube (53, 58) together can be easilyset, and therefore it can be further ensured that the fin (236) and theflat tube (53, 58) can be joined together. Moreover, the end of the flattube (53, 58) is aligned with the end of the cut part (245) on the openside thereof. Thus, if the flat tubes (53, 58) having different widthsare used, the depth of the cut part (245) may be set corresponding tothe flat tube (58) having a greater width. That is, even if plural typesof flat tubes (53, 58) having different widths are used, the common fin(236) can be used.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a refrigerant circuit diagram of an air conditioner of a firstembodiment, and illustrates a state in an air-cooling operation.

FIG. 2 is a refrigerant circuit diagram of the air conditioner of thefirst embodiment, and illustrates a state in an air-heating operation.

FIG. 3 is a schematic perspective view of a heat exchanger unit formingan outdoor heat exchanger of the first embodiment.

FIG. 4 is a schematic front view of the heat exchanger unit forming theoutdoor heat exchanger of the first embodiment.

FIG. 5 is an enlarged perspective view of a main part of the heatexchanger unit of the first embodiment in the state in which part of themain part is not shown.

FIG. 6 is a schematic view illustrating an example of a cross-sectionalshape of a flat tube.

FIG. 7A is a view illustrating an example of a cross-sectional shape ofa refrigerant flow path in the flat tube for a main heat exchange part.FIG. 7B is a view illustrating an example of a cross-sectional shape ofa refrigerant flow path in the flat tube for an auxiliary heat exchangepart.

FIG. 8 is an view illustrating part of a cross section of a heatexchanger of a first variation of the first embodiment.

FIG. 9 is a schematic perspective view of a fin provided in the heatexchanger of the first variation.

FIGS. 10A and 10B are views illustrating a heat transfer part providedin the fin of the heat exchanger of the first variation. FIG. 10A is thefront view of the heat transfer part. FIG. 10B is the cross-sectionalview along a B-B line illustrated in FIG. 10A.

FIG. 11A is a partial cross-sectional view of a heat exchanger of asecond variation. FIG. 11B is a cross-sectional view of a fin along aV-V line illustrated in FIG. 11A.

FIG. 12 is a view illustrating part of a cross section of a heatexchanger of a third variation of the first embodiment.

FIGS. 13A and 13B are views illustrating a main part of a fin of theheat exchanger of the third variation. FIG. 13A is the front view of thefin. FIG. 13B is the cross-sectional view along a G-G line illustratedin FIG. 13A.

FIG. 14A is a partial cross-sectional view of a heat exchanger of afourth variation. FIG. 14B is a cross-sectional view of a fin along anX-X line illustrated in FIG. 14A.

FIG. 15 is a front view illustrating a schematic configuration of anoutdoor heat exchanger of a second embodiment.

FIG. 16 is a partial cross-sectional view illustrating a front side ofthe outdoor heat exchanger of the second embodiment.

FIG. 17 is a front view illustrating a schematic configuration of anoutdoor heat exchanger of a third embodiment.

FIG. 18 is a partial cross-sectional view illustrating a front side ofthe outdoor heat exchanger of the third embodiment.

FIG. 19 is a front view illustrating a schematic configuration of anoutdoor heat exchanger of a fourth embodiment.

FIG. 20 is a partial cross-sectional view illustrating a front side ofthe outdoor heat exchanger of the fourth embodiment.

FIG. 21 is a front view illustrating a schematic configuration of anoutdoor heat exchanger of a fifth embodiment.

FIG. 22 is a partial cross-sectional view illustrating a front side ofthe outdoor heat exchanger of the fifth embodiment.

FIG. 23 is a front view illustrating a schematic configuration of anoutdoor heat exchanger of a sixth embodiment.

FIG. 24 is a partial cross-sectional view illustrating a front side ofthe outdoor heat exchanger of the sixth embodiment.

FIG. 25 is a partial cross-sectional view of an outdoor heat exchangerof a seventh embodiment.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure will be described below withreference to drawings. Note that the embodiments described below will beset forth merely for the purpose of preferred examples in nature, andare not intended to limit the scope, applications, and use of theinvention.

First Embodiment of the Invention

A first embodiment of the present disclosure will be described. Thepresent embodiment is intended for an air conditioner including arefrigerating apparatus.

Entire Configuration of Air Conditioner

FIG. 1 is a refrigerant circuit diagram of an air conditioner (10) ofthe first embodiment of the present disclosure, and illustrates a statein an air-cooling operation. Moreover, FIG. 2 is a refrigerant circuitdiagram of the air conditioner (10) of the first embodiment, andillustrates a state in an air-heating operation. Referring to FIG. 1,the air conditioner (10) of the present embodiment includes a singleindoor unit (12) which is a utilization-side unit, and a single outdoorunit (11) which is a heat-source-side unit. In the air conditioner (10),the outdoor unit (11) and the indoor unit (12) are connected together bypipes to form a refrigerant circuit (20).

Note that the number of indoor units (12) and outdoor units (11) hasbeen set forth merely for the purpose of an example. That is, in the airconditioner (10) of the present embodiment, a plurality of indoor units(12) may be connected to a single outdoor unit (11) to form arefrigerant circuit (20). Alternatively, a plurality of outdoor units(11) and a plurality of indoor units (12) may be connected together toform a refrigerant circuit (20).

In the refrigerant circuit (20), the followings are provided: acompressor (31); an outdoor heat exchanger (40) which is aheat-source-side heat exchanger; an indoor heat exchanger (32) which isa utilization-side heat exchanger; an expansion valve (33); and afour-way valve (34). The compressor (31), the outdoor heat exchanger(40), the expansion valve (33), and the four-way valve (34) areaccommodated in the outdoor unit (11). The indoor heat exchanger (32) isaccommodated in the indoor unit (12). Although not shown in the figure,an outdoor fan configured to supply outdoor air to the outdoor heatexchanger (40) is provided in the outdoor unit (11), and an indoor fanconfigured to supply indoor air to the indoor heat exchanger (32) isprovided in the indoor unit (12).

The compressor (31) is a hermetic rotary compressor or a hermetic scrollcompressor. In the refrigerant circuit (20), an outlet pipe of thecompressor (31) is connected to a first port of the four-way valve (34)through a pipe, and an inlet pipe of the compressor (31) is connected toa second port of the four-way valve (34) through a pipe.

The outdoor heat exchanger (40) includes first and second header members(46, 47) standing upright, and a plurality of heat transfer pipes(hereinafter also referred to as “flat tubes”) (53, 58). The outdoorheat exchanger (40) is configured to exchange heat between refrigerantand outdoor air. The structure of the outdoor heat exchanger (40) willbe described in detail later. The indoor heat exchanger (32) is aso-called “cross-fin type fin-and-tube heat exchanger,” and isconfigured to exchange heat between refrigerant and indoor air.

The expansion valve (33) is a so-called “electronic expansion valve(33).” The four-way valve (34) includes four ports, and switches betweena first state (state illustrated in FIG. 1) in which the first portcommunicates with a third port and the second port communicates with afourth port and a second state (state illustrated in FIG. 2) in whichthe first port communicates with the fourth port and the second portcommunicates with the third port.

In the refrigerant circuit (20), a first gas pipe (21), a second gaspipe (22), and a liquid pipe (23) are provided. The first gas pipe (21)is, at one end thereof, connected to the third port of the four-wayvalve (34), and is, at the other end thereof, connected to an upper endpart of the first header member (46) of the outdoor heat exchanger (40).The second gas pipe (22) is, at one end thereof, connected to the fourthport of the four-way valve (34), and is, at the other end thereof,connected to a gas end of the indoor heat exchanger (32). The liquidpipe (23) is, at one end thereof, connected to a lower end part of afirst header collecting pipe (56) which will be described later, and is,at the other end thereof, connected to a liquid end of the indoor heatexchanger (32). The expansion valve (33) is provided in the middle ofthe liquid pipe (23).

Structure of Outdoor Heat Exchanger

The structure of the outdoor heat exchanger (40) will be described indetail with reference to FIGS. 3, 4, and 5. FIG. 3 is a schematicperspective view of a heat exchanger unit forming the outdoor heatexchanger of the first embodiment. FIG. 4 is a schematic front view ofthe heat exchanger unit forming the outdoor heat exchanger of the firstembodiment. FIG. 5 is an enlarged perspective view of a main part of theheat exchanger unit of the first embodiment in the state in which partof the main part is not shown.

The outdoor heat exchanger (40) of the present embodiment includes asingle heat exchanger unit (45).

Referring to FIGS. 3 and 4, the heat exchanger unit (45) forming theoutdoor heat exchanger (40) includes the single first header member(46), the single second header member (47), the plurality of heattransfer pipes (53, 58), and a plurality of fins (54, 59). The firstheader member (46), the second header member (47), the flat tubes (53,58), and the fins (54, 59) are members made of an aluminum alloy, andare joined together by brazing. The fin (54, 59) divides part betweenadjacent ones of the flat tubes (53, 58) into a plurality of airpassages through each of which air flows.

The first header member (46) and the second header member (47) are eachformed in an elongated hollow cylindrical shape closed at both endsthereof. In FIG. 4, the first header member (46) stands upright at theleft of the heat exchanger unit (45), and the second header member (47)stands upright at the right of the heat exchanger unit (45). That is,the first header member (46) and the second header member (47) aremounted in such an attitude that the axial directions thereof are alongthe vertical direction.

Referring to FIG. 5, the heat transfer pipes (53, 58) are each formed ina flat shape, and a plurality of refrigerant flow paths (49) are fannedin line in each of the heat transfer pipes (53, 58). The heat transferpipes (53, 58) are hereinafter also referred to as “flat tubes.” FIG. 6is a schematic view illustrating an example of a cross-sectional shapeof the flat tube (53, 58). In this example, the width (W2) of the flattube (58) is, referring to FIG. 6, greater than the width (W1) of theflat tube (53). Moreover, the number of flow paths per flat tube (58) isgreater than the number of flow paths per flat tube (53).

FIG. 7A is a view illustrating an example of a cross-sectional shape ofthe refrigerant flow path (49) in the flat tube (53) for a main heatexchange part (50) which will be described later, and FIG. 7B is a viewillustrating an example of a cross-sectional shape of the refrigerantflow path (49) in the flat tube (58) for an auxiliary heat exchange part(55) which will be described later. In the example illustrated in FIGS.7A and 7B, a plurality of grooves (49 a) are formed in each of therefrigerant flow paths (49) of the flat tube (53), whereas the flat tube(58) is a so-called “bare pipe (smooth inner pipe)” having a circularcross section. That is, no groove (49 a) is formed in each of therefrigerant flow paths (49) of the flat tube (58). Note that, in thisexample, each of the refrigerant flow paths (49) of the flat tube (58)has a diameter of about 0.5 mm. Needless to say, such cross-sectionalshapes of the refrigerant flow path (49) are set forth merely for thepurpose of examples, and other shapes (e.g., a rectangular cross sectionillustrated in FIG. 6) may be employed.

In the heat exchanger unit (45), the flat tubes (53, 58) are arranged atpredetermined intervals in the axial direction of the first and secondheader members (46, 47) in such an attitude that the axial direction ofthe flat tube (53, 58) is along the horizontal direction and sidesurfaces of the flat tubes (53, 58) face each other. That is, in theheat exchanger unit (45), the flat tubes (53, 58) are arranged parallelto each other between the first header member (46) and the second headermember (47). One end part of the flat tube (53, 58) is inserted into thefirst header member (46), and the other end part of the flat tube (53,58) is inserted into the second header member (47). Each of therefrigerant flow paths (49) in the flat tube (53, 58) communicates, atone end thereof, with an internal space of the first header member (46),and communicates, at the other end thereof, with an internal space ofthe second header member (47).

The fin (54, 59) is provided between adjacent ones of the flat tubes(53, 58). The fin (54, 59) is formed in a corrugated plate shapemeandering up and down, and is mounted in such an attitude that a ridgeline of such a wave shape is along the front-back direction (directionperpendicular to the plane of paper of FIG. 4) of the heat exchangerunit (45). In the heat exchanger unit (45), air passes in the directionperpendicular to the plane of paper of FIG. 4.

Referring to FIG. 4, a discoid partition plate (48) is provided in thefirst header member (46). The internal space of the first header member(46) is horizontally divided by the partition plate (48). On the otherhand, the internal space of the second header member (47) is a singleundivided space.

In the heat exchanger unit (45), the upper part relative to thepartition plate (48) forms the main heat exchange part (50), and thelower part relative to the partition plate (48) forms the auxiliary heatexchange part (55).

Specifically, in the first header member (46), the upper part relativeto the partition plate (48) forms a first header collecting pipe (51) ofthe main heat exchange part (50), and the lower part relative to thepartition plate (48) forms the first header collecting pipe (56) of theauxiliary heat exchange part (55). Of the flat tubes (53, 58) providedin the heat exchanger unit (45), the flat tubes (53) connected to thefirst header collecting pipe (51) of the main heat exchange part (50)are for the main heat exchange part (50), and the flat tubes (58)connected to the first header collecting pipe (56) of the auxiliary heatexchange part (55) are for the auxiliary heat exchange part (55). Of thefins (54, 59) provided in the heat exchanger unit (45), the fins (54)each provided between adjacent ones of the flat tubes (53) of the mainheat exchange part (50) are for the main heat exchange part (50), andthe fins (59) each provided between adjacent ones of the flat tubes (58)of the auxiliary heat exchange part (55) are for the auxiliary heatexchange part (55). In the second header member (47), part of the secondheader member (47) to which the flat tubes (53) of the main heatexchange part (50) are inserted forms a second header collecting pipe(52) of the main heat exchange part (50), and part of the second headermember (47) to which the flat tubes (58) of the auxiliary heat exchangepart (55) arc inserted forms a second header collecting pipe (57) of theauxiliary heat exchange part (55).

In the outdoor heat exchanger (40), the width (W1) of the flat tube (53)of the main heat exchange part (50), the number of refrigerant flowpaths (49), the cross-sectional area of the refrigerant flow path (49),the number of flat tubes (53), etc. are determined based on requirementsof a heat exchange capacity required for air-cooing and air-heating. Ingeneral, the number of flat tubes (53, 58) which can be provided in theoutdoor heat exchanger (40) is limited. Thus, e.g., the number of flattubes (58) is the number obtained by subtracting the number of flattubes (53) from the maximum possible number. Then, based on thedetermined number of flat tubes (53, 58), the width (W2) of the flattube (58), the number of refrigerant flow paths (49), and thecross-sectional area of the refrigerant flow path (49) are set dependingon the capacity required for the auxiliary heat exchange part (55).

Specifically, in the outdoor heat exchanger (40) of the presentembodiment, the number of flat tubes (58) of the auxiliary heat exchangepart (55) is less than the number of flat tubes (53) of the main heatexchange part (50). The total cross-sectional area of refrigerant flowpaths (49) per flat tube (58) provided in the auxiliary heat exchangepart (55) is greater than the total cross-sectional area of refrigerantflow paths (49) per flat tube (53) provided in the main heat exchangepart (50).

In this example, sixty flat tubes (53, 58) are provided in the outdoorheat exchanger (40). The number of flat tubes (58) of the auxiliary heatexchange part (55) is ten, and the number of flat tubes (53) of the mainheat exchange part (50) is fifty. That is, the number of flat tubes (58)of the auxiliary heat exchange part (55) is one-fifth of the number offlat tubes (53) of the main heat exchange part (50). Note that thenumber of flat tubes (53, 58) illustrated in FIGS. 3 and 4 is differentfrom the actual number of flat tubes (53, 58) provided in the outdoorheat exchanger (40).

As described above, in the refrigerant circuit (20), the first gas pipe(21) is connected to the upper end part of the first header member (46),and the liquid pipe (23) is connected to a lower end part of the firstheader member (46) (see FIG. 1). That is, in the outdoor heat exchanger(40), the first gas pipe (21) is connected to the first headercollecting pipe (51) of the main heat exchange part (50), and the liquidpipe (23) is connected to the first header collecting pipe (56) of theauxiliary heat exchange part (55).

Operations

The operations of the air conditioner (10) will be described. The airconditioner (10) performs the air-cooling operation which is a coolingprocess and the air-heating operation which is a heating process.

Air-Cooling Operation

The process in the air-cooling operation of the air conditioner (10)will be described with reference to FIG. 1.

In the air-cooling operation, the four-way valve (34) is set at thefirst state. Moreover, the degree of opening of the expansion valve (33)is adjusted such that the degree of superheat of refrigerant flowing outfrom the gas end of the indoor heat exchanger (32) reaches apredetermined target value (e.g., 5° C.). Further, in the air-coolingoperation, outdoor air is supplied to the outdoor heat exchanger (40) bythe outdoor fan, and indoor air is supplied to the indoor heat exchanger(32) by the indoor fan.

In the refrigerant circuit (20), refrigerant discharged from thecompressor (31) passes through the four-way valve (34) and the first gaspipe (21) in this order, and then flows into the first header collectingpipe (51) of the main heat exchange part (50). The refrigerant flowinginto the first header collecting pipe (51) flows into the flat tubes(53) of the main heat exchange part (50). While passing through each ofthe refrigerant flow paths (49) of the flat tubes (53), the refrigerantis condensed by dissipating heat to outdoor air. After passing throughthe flat tubes (53), the refrigerant flows into the second headercollecting pipe (52) of the main heat exchange part (50), and then flowsdown to the second header collecting pipe (57) of the auxiliary heatexchange part (55). The refrigerant flowing into the second headercollecting pipe (57) flows into the flat tubes (58) of the auxiliaryheat exchange part (55). While passing through each of the refrigerantflow paths (49) of the flat tubes (58), the refrigerant enters asub-cooling state by dissipating heat to outdoor air. After passingthrough the flat tubes (58), the refrigerant flows into the first headercollecting pipe (56) of the auxiliary heat exchange part (55).

The refrigerant flowing into the liquid pipe (23) from the first headercollecting pipe (56) of the auxiliary heat exchange part (55) isexpanded (i.e., the pressure of refrigerant is reduced) upon passage ofthe expansion valve (33), and then flows into the liquid end of theindoor heat exchanger (32). The refrigerant flowing into the indoor heatexchanger (32) is evaporated by absorbing heat from indoor air. Theindoor unit (12) supplies taken indoor air to the indoor heat exchanger(32), and sends indoor air cooled by the indoor heat exchanger (32) backto a room.

The refrigerant evaporated in the indoor heat exchanger (32) flows intothe second gas pipe (22) from the gas end of the indoor heat exchanger(32). Subsequently, the refrigerant is sucked into the compressor (31)through the four-way valve (34). The compressor (31) compresses thetaken refrigerant and then discharge the compressed refrigerant.

Air-Heating Operation

The process in the air-heating operation of the air conditioner (10)will be described with reference to FIG. 2.

In the air-heating operation, the four-way valve (34) is set at thesecond state. Moreover, the degree of opening of the expansion valve(33) is adjusted such that the degree of superheat of refrigerantflowing out from the outdoor heat exchanger (40) reaches a predeterminedtarget value (e.g., 5° C.). Further, in the air-heating operation,outdoor air is supplied to the outdoor heat exchanger (40) by theoutdoor fan, and indoor air is supplied to the indoor heat exchanger(32) by the indoor fan.

In the refrigerant circuit (20), refrigerant discharged from thecompressor (31) passes through the four-way valve (34) and the secondgas pipe (22) in this order, and then flows into the gas end of theindoor heat exchanger (32). The refrigerant flowing into the indoor heatexchanger (32) is condensed by dissipating heat to indoor air. Theindoor unit (12) supplies taken indoor air to the indoor heat exchanger(32), and sends indoor air heated by the indoor heat exchanger (32) backto a room.

The refrigerant flowing into the liquid pipe (23) from the liquid end ofthe indoor heat exchanger (32) is expanded (i.e., the pressure ofrefrigerant is reduced) upon passage of the expansion valve (33), andthen flows into the first header collecting pipe (56) of the auxiliaryheat exchange part (55). The refrigerant flowing into the first headercollecting pipe (56) of the auxiliary heat exchange part (55) flows intothe flat tubes (58) of the auxiliary heat exchange part (55). Whilepassing through the refrigerant flow paths (49), the refrigerant flowinginto each of the flat tubes (58) absorbs heat from outdoor air, and partof the refrigerant is evaporated. The refrigerant evaporated in the flattubes (58) flows into the second header collecting pipe (52), and thenflows into the flat tubes (53) of the main heat exchange part (50).While passing through the refrigerant flow paths (49), the refrigerantflowing into each of the flat tubes (53) is evaporated by absorbing heatfrom outdoor air.

After passing through the flat tubes (53) of the main heat exchange part(50), the refrigerant flows into the first header collecting pipe (51)of the main heat exchange part (50), and then flows into the first gaspipe (21). After passing through the four-way valve (34), therefrigerant flowing through the first gas pipe (21) is sucked into thecompressor (31). The compressor (31) compresses the taken refrigerantand discharges the compressed refrigerant.

Advantages of the Present Embodiment

In the present embodiment, the number of flat tubes (58) forming theauxiliary heat exchange part (55) is less than the number of flat tubes(53) forming the main heat exchange part (50). However, the totalcross-sectional area of refrigerant flow paths (49) per flat tube (58)provided in the auxiliary heat exchange part (55) is greater than thetotal cross-sectional area of refrigerant flow paths (49) per flat tube(53) provided in the main heat exchange part (50). Thus, in the casewhere the heat exchanger serves as a condenser, the flow velocity ofrefrigerant in the auxiliary heat exchange part (55) can be lowered ascompared to, e.g., a heat exchanger (hereinafter, for the sake ofsimplicity of description, referred to as a “conventional heatexchanger”) in which a single type of flat tubes fauns a main heatexchanger part and an auxiliary heat exchange part. Consequently,according to the present embodiment, a pressure loss in the auxiliaryheat exchange part (55) can be reduced.

In the present embodiment, the number of flow paths per flat tube (53,58) and the width (W1, W2) of the flat tube (53, 58) are adjusted sothat the total cross-sectional area of refrigerant flow paths (49) perflat tube (53, 58) can be set. Thus, the total cross-sectional area ofrefrigerant flow paths (49) in the flat tube (53) for the main heatexchange part (50) and the total cross-sectional area of refrigerantflow paths (49) in the flat tube (58) for the auxiliary heat exchangepart (55) can be easily set.

In the present embodiment, the grooves (49 a) are formed in each of therefrigerant flow paths (49) of the flat tube (53) in the main heatexchange part (50). Thus, in the flat tube (53), the surface area perrefrigerant flow path (49) can be increased. That is, a heat exchangeefficiency in the main heat exchange part (50) can be improved.

Since the flat tube (58) of the auxiliary heat exchange part (55) is theso-called “bare pipe,” a pressure loss due to a pipe shape can bereduced as compared to the flat tube (53) of the main heat exchange part(50).

The refrigerant flow path (49) has, as described above, anextremely-small diameter. Thus, when the outdoor heat exchanger (40) ismanufactured at a factory, if, e.g., flat tubes having the same widthform a main heat exchange part and an auxiliary heat exchange part, itis difficult to identify, with eyes, the presence/absence of the grooves(49 a) of the refrigerant flow path (49). However, in the presentembodiment, since the flat tube (53) for the main heat exchange part(50) and the flat tube (58) for the auxiliary heat exchange part (55)have the different widths (W1, W2), the presence/absence of the grooves(49 a) of the refrigerant flow path (49) can be easily identified.

First Variation of First Embodiment

The configuration of the fins (54, 59) has been set forth merely for thepurpose of an example, and various types of fins may be employed for theheat exchanger (40). For example, a fin illustrated in FIG. 8 may beemployed, instead of the fins (54, 59). FIG. 8 is a view illustratingpart of a cross section of a heat exchanger (40) of a first variation ofthe first embodiment. A fin (235) is a corrugated fin meandering up anddown, and is arranged between adjacent ones of flat tubes (heat transferpipes) (53, 58) which are respectively at the top and bottom of the fin(235). Although will be described in detail later, a plurality of heattransfer parts (237) and a plurality of middle plate parts (241) areformed in the fin (235). In the fin (235), the middle plate parts (241)are joined to the flat tube (53, 58) by brazing.

Configuration of Fin

FIG. 9 is a schematic perspective view of the fin (235) provided in theheat exchanger (40) of the first variation. Referring to FIG. 9, the fin(235) is the corrugated fin formed in such a manner that a metal platehaving a uniform width is bent, and is in the shape meandering up anddown. In the fin (235), the heat transfer parts (237) and the middleplate parts (241) are alternately formed along an extension direction ofthe flat tube (53, 58). That is, in the fin (235), the plurality of heattransfer parts (237) arranged in the extension direction of the flattube (53, 58) are provided between the adjacent ones of the flat tubes(53, 58). Moreover, in the fin (235), protruding plate parts (242) arefoamed. Note that louvers (250, 260, 270) and a water guide rib (271)which will be described later are not shown in FIG. 9.

The heat transfer part (237) is a plate-shaped part extending from oneof adjacent ones of the flat tubes (53, 58) to the other one of theadjacent ones of the flat tubes (53, 58). In the heat transfer part(237), an end part thereof on a windward side is a front edge (238).Although not shown in FIG. 9, the plurality of louvers (250, 260) areformed in the heat transfer part (237). The middle plate part (241) is aplate-shaped part along flat side surfaces of the flat tubes (53, 58),and is continuous to upper ends of adjacent ones of the heat transferparts (237) or lower ends of adjacent ones of the heat transfer parts(237). The angle formed between the heat transfer part (237) and themiddle plate part (241) is the substantially right angle.

The protruding plate part (242) is a plate-shaped part continuouslyformed with an end part of the heat transfer part (237) on a leewardside. The protruding plate part (242) is formed in avertically-elongated plate shape, and protrudes beyond the flat tube(53, 58) toward the leeward side. An upper end of the protruding platepart (242) upwardly protrudes beyond the upper end of the heat transferpart (237), and a lower end of the protruding plate part (242)downwardly protrudes beyond the lower end of the heat transfer part(237). Referring to FIG. 8, in the outdoor heat exchanger (40), adjacentones of the protruding plate parts (242) of the fins (235) sandwichingthe flat tube (53, 58) at the top and bottom thereof contact each other.In the protruding plate part (242) of the fin (235), the water guide rib(271) is formed. The water guide rib (271) is an elongated recessedgroove vertically extending along an end part of the protruding platepart (242) on the leeward side.

FIGS. 10A and 10B are views illustrating the heat transfer part (237)provided in the fin (235) of the outdoor heat exchanger (40) of thefirst variation. FIG. 10A is a front view of the heat exchange part, andFIG. 10B is a cross-sectional view along a B-B line illustrated in FIG.10A. Referring to FIGS. 10A and 10B, in the heat transfer part (237) andthe protruding plate part (242) of the fin (235), the plurality oflouvers (250, 260, 270) are formed. The louver (250, 260, 270) is formedin such a manner that part of the heat transfer part (237) or theprotruding plate part (242) is cut and is folded up. That is, thelouvers (250, 260, 270) are formed in such a manner that a plurality ofslit-shaped cut is formed in the heat transfer part (237) and theprotruding plate part (242) and part between adjacent ones of the cutsis plastically deformed by twisting.

Second Variation of First Embodiment

FIG. 11A is a partial cross-sectional view of a heat exchanger (40) of asecond variation, and FIG. 11B is a cross-sectional view of a fin alonga V-V line illustrated in FIG. 11A. In this example, a plurality ofwaffle parts (251, 252, 253) are formed, instead of the louvers (250,260, 270) described in the first variation. Referring to FIGS. 11A and11B, in a heat transfer part (237) and a protruding plate part (242) ofa fin (235), the plurality of waffle parts (251, 252, 253) are fanned.The waffle part (251, 252, 253) is a protrusion protruding toward a sideon which an air passage is formed and formed in a vertically elongatedshape. The waffle parts (251, 252, 253) are formed in such a manner thatpart of the heat transfer part (237) is plastically deformed by, e.g.,pressing. The waffle part (251, 252, 253) extends in a directioninclined relative to the vertical direction such that a lower end partof the waffle part (251, 252, 253) is positioned on the leeward siderelative to an upper end part thereof.

The waffle part (251, 252, 253) has a pair of vertically-elongatedtrapezoidal surfaces (254) and a pair of flat upper and lower triangularsurfaces (255). The trapezoidal surfaces (254) are adjacent to eachother in an air passage direction so as to form a ridge part (256)forming a ridge line. The triangular surfaces (255) are formedrespectively at the top and bottom of the ridge part (256).

In the heat transfer part (237), the plurality of waffle parts (251,252, 253) are formed so as to be arranged from the windward side to theleeward side. The waffle parts (251, 252, 253) are the singlewindward-side waffle part (251) formed on the windward side of the heattransfer part (237), the two leeward-side waffle parts (253) formed onthe leeward side of the heat transfer part (237), and the single middlewaffle part (252) formed between the windward-side waffle part (251) andthe leeward-side waffle part (253). Of the waffle parts (251, 252, 253),the windward-side waffle part (251) is a windward-side protrusion formedon the most windward side. Of the waffle parts (251, 252, 253), theleeward-side waffle part (253) is a leeward-side protrusion formed onthe most leeward side.

An upper end of the windward-side waffle part (251) is positioned lowerthan that of the leeward-side waffle part (253). Moreover, an upper endof the middle waffle part (252) and the upper end of the leeward-sidewaffle part (253) are at the substantially same height. The upper end ofthe windward-side waffle part (251), the upper end of the middle wafflepart (252), and the upper ends of the leeward-side waffle part (253) aresubstantially parallel to a flat surface of a flat tube (53, 58)provided on an upper side thereof.

A lower end of the windward-side waffle part (251) is positioned higherthan that of the leeward-side waffle part (253). The lower end of thewindward-side waffle part (251) is inclined such that part of the lowerend of the windward-side waffle part (251) on the leeward side ispositioned lower than that on the windward side. A lower end of themiddle waffle part (252) is also inclined such that part of the lowerend of the middle waffle part (252) on the leeward side is positionedlower than that on the windward side. The lower end of the leeward-sidewaffle parts (253) are substantially parallel to the flat surface of theflat tube (53, 58).

Third Variation of First Embodiment

A fin illustrated in FIG. 12 may be employed, instead of the fins (54,59). FIG. 12 is a view illustrating part of a cross section of a heatexchanger (40) of a third variation of the first embodiment.

Configuration of Fin

Referring to FIG. 12, a fin (236) is an elongated plate-shaped finformed in such a manner that a metal plate is pressed. In the fin (236),a plurality of elongated cut parts (245) each extending from a frontedge (238) of the fin (236) in a width direction of the fin (236) areformed. In the fin (236), the cut parts (245) are formed atpredetermined intervals in a longitudinal direction of the fin (236).Part of the cut part (245) on the leeward side forms a pipe insertionpart (246). The pipe insertion part (246) has a vertical widthsubstantially equal to the thickness of a flat tube (53, 58). Moreover,the length (depth) of the pipe insertion part (246) is substantiallyequal to the width of the flat tube (58) having a greater width. Sincethe depth of the pipe insertion part (246) corresponds, as describedabove, to the width of the flat tube (58) having a greater width, asingle type of fins (236) can be used. That is, plural types of moldsare not necessarily prepared for manufacturing of the fins (236), andreduction in manufacturing cost can be expected. The flat tube (53, 58)is inserted into a corresponding one of the pipe insertion parts (246)of the fin (236), and is joined to a peripheral edge part of the pipeinsertion part (246) by brazing. In the present embodiment, an end ofthe flat tube (53, 58) in a width direction thereof is aligned with anend of the cut part (245) on an open side thereof. Since the length ofthe pipe insertion part (246) corresponds to the width (W2) of the flattube (58), a clearance is formed on a closed side of the pipe insertionpart (246) in the state in which the flat tube (53) is inserted into thepipe insertion part (246).

For example, the fin (236) and the flat tube (53, 58) are brazed witheach other as follows. First, a side of the fin (236) close to the cutpart (245) (i.e., the left side as viewed in FIG. 12) faces up. Then,the end of the flat tube (53, 58) in the width direction thereof is setso as to be aligned with the end of the inlet side of the cut part (245)on the open side thereof, more specifically an end of the pipe insertionpart (246) on an open side thereof (i.e., the left end as viewed in FIG.12). A brazing material is applied in a linear shape at a position (A)illustrated in FIG. 12. Note that the application position (A) isillustrated only for one of the flat tubes (53) in FIG. 12, but the sameapplies to the other flat tubes (53, 58). If an attempt is made to causethe flat tube (53) to contact the deepest part of the pipe insertionpart (246), the brazing material drops, upon brazing, into the pipeinsertion part (246), and therefore it is difficult to set the brazingmaterial. However, in the present embodiment, since the end of the flattube (53, 58) in the width direction thereof is aligned with the end ofthe cut part (245) on the open side thereof as described above, thebrazing material can be easily set.

Subsequently, e.g., the heat exchanger (40) is placed in a heatingfurnace (not shown in the figure), and the brazing material is melted.This allows the brazing material to flow along the flat tube (53, 58),and therefore the fin (236) and the flat tube (53, 58) are joinedtogether.

In the fin (236), part between adjacent ones of the cut parts (245)fauns a heat transfer part (237), and part of the pipe insertion part(246) on the leeward side forms a leeward-side plate part (247). Thatis, in the fin (236), a plurality of heat transfer parts (237) adjacentto each other with the flat tube (53, 58) being interposed betweenadjacent ones of the heat transfer parts (237), and a singleleeward-side plate part (247) continuously formed in end parts of theheat transfer parts (237) on the leeward side are provided. In the heatexchanger (40), each of the heat transfer parts (237) of the fin (236)is arranged between adjacent ones of the flat tubes (53, 58) arranged inthe vertical direction, and the leeward-side plate part (247) protrudesbeyond the flat tubes (53, 58) toward the leeward side.

FIGS. 13A and 13B are views illustrating a main part of the fin (236) ofthe heat exchanger (40) of the third variation. FIG. 13A is a front viewof the fin (236), and FIG. 13B is a cross-sectional view along a G-Gline illustrated in FIG. 13A. Referring to FIG. 13, in the heat transferpart (237) and the leeward-side plate part (247), a plurality of louvers(250, 260) are formed. The louver (250, 260) is formed in such a mannerthat part of the heat transfer part (237) or the leeward-side plate part(247) is cut and is folded up.

Fourth Variation of First Embodiment

FIG. 14A is a partial cross-sectional view of a heat exchanger (40) of afourth variation, and FIG. 14B is a cross-sectional view of a fin (236)along an X-X line illustrated in FIG. 14A. In this example, waffle parts(251, 252, 253) are, instead of the louvers (250, 260), formed in theplate-shaped fin described in the third variation. The waffle parts(251, 252, 253) has a configuration similar to that described in thesecond variation.

Second Embodiment of the Invention

An outdoor heat exchanger of a second embodiment of the presentdisclosure will be described. FIG. 15 is a front view illustrating aschematic configuration of the outdoor heat exchanger (40) of the secondembodiment. Moreover, FIG. 16 is a partial cross-sectional viewillustrating a front side of the outdoor heat exchanger (40) of thesecond embodiment.

Referring to FIG. 15, the outdoor heat exchanger (40) is divided intothree heat exchange parts (350 a-350 c). Specifically, in the outdoorheat exchanger (40), the first exchange part (350 a), the secondexchange part (350 b), and the third exchange part (350 c) are formed inthis order from the bottom to the top.

Referring to FIG. 16, in each of a first header collecting pipe (360)and a second header collecting pipe (370), three communication spaces(361 a-361 c, 371 a-371 c) are formed in such a manner that each ofinner spaces of the first header collecting pipe (360) and the secondheader collecting pipe (370) is divided by partition plates (339).

The communication space (361 a-361 c) of the first header collectingpipe (360) is further horizontally divided by a partition plate (339).In the communication space (361 a-361 c) of the first header collectingpipe (360), the lower space is a lower space (362 a-362 c) which is afirst space, and the upper space is an upper space (363 a-363 c) whichis a second space.

The exchange part (350 a-350 c) of the outdoor heat exchanger (40) isdivided into a main heat exchange region (main heat exchange part) (351a-351 c) and an auxiliary heat exchange region (auxiliary heat exchangepart) (352 a-352 c). In the exchange part (350 a-350 c), eleven flattubes (53) communicating with a corresponding one of the upper spaces(363 a-363 c) of the first header collecting pipe (360) form the mainheat exchange part (351 a-351 c), and three flat tubes (58)communicating with a corresponding one of the lower spaces (362 a-362 c)of the first header collecting pipe (360) form the auxiliary heatexchange part (352 a-352 c).

In the present embodiment, the width of the flat tube (58) provided inthe auxiliary heat exchange part (352 a-352 c) is, as in the firstembodiment, greater than that of the flat tube (53) provided in the mainheat exchange part (351 a-351 c). Moreover, the number of flow paths perflat tube (58) provided in the auxiliary heat exchange part (352 a-352c) is greater than the number of flow paths per flat tube (53) providedin the main heat exchange part (351 a-351 c). In this example, fins(corrugated fins) (235) are employed as fins. Needless to say, the fins(54, 59) described in the first embodiment or the fins (236) describedin the other variations may be employed.

Referring to FIG. 15, in the outdoor heat exchanger (40), a liquidconnection member (380) and a gas header (385) are provided. The liquidconnection member (380) and the gas header (385) are attached to thefirst header collecting pipe (360).

The liquid connection member (380) includes a single distributor (381)and three thin pipes (382 a-382 c). A pipe connecting between theoutdoor heat exchanger (40) and an expansion valve (33) is connected toa lower end part of the distributor (381). The thin pipe (382 a-382 c)is, at one end thereof, connected to an upper end part of thedistributor (381). In the distributor (381), the pipe connected to thelower end part thereof and the thin pipes (382 a-382 c) communicate witheach other. The thin pipe (382 a-382 c) is, at the other end, connectedto the first header collecting pipe (360), and communicates with acorresponding one of the lower spaces (362 a-362 c).

The gas header (385) includes a single main pipe part (386) and threeconnection pipe parts (387 a-387 c). The main pipe part (386) is formedin a pipe shape curving in an inverted U-shape at an upper part thereofand having a relatively-large diameter. A pipe connecting between theoutdoor heat exchanger (40) and a third port of a four-way valve (34) isconnected to an upper end part of the main pipe part (386). A lower endpart of the main pipe part (386) is closed. The connection pipe parts(387 a-387 c) laterally protrude from a straight part of the main pipepart (386).

According to the foregoing configuration, in the outdoor heat exchanger(40) of the present embodiment, refrigerant flows in a directionindicated by arrows illustrated in FIG. 15 in an air-cooling operation.In an air-heating operation, refrigerant flows in a direction oppositeto the direction indicated by the arrows illustrated in FIG. 15.

Third Embodiment of the Invention

An outdoor heat exchanger of a third embodiment of the presentdisclosure will be described. FIG. 17 is a front view illustrating aschematic configuration of the outdoor heat exchanger (40) of the thirdembodiment. Moreover, FIG. 18 is a partial cross-sectional viewillustrating a front side of the outdoor heat exchanger (40) of thethird embodiment.

Referring to FIGS. 17 and 18, the outdoor heat exchanger (40) includes asingle first header collecting pipe (460), a single second headercollecting pipe (470), a plurality of flat tubes (53, 58), and aplurality of fins (235).

Referring to FIG. 17, the flat tubes (53, 58) of the outdoor heatexchanger (40) are divided for two upper and lower heat exchange regions(451, 452). That is, in the outdoor heat exchanger (40), the upper heatexchange region (451) and the lower heat exchange region (452) areformed. The heat exchange region (451, 452) is horizontally divided intothree heat exchange parts (451 a-451 c, 452 a-452 c). Specifically, inthe upper heat exchange region (451), the first main heat exchange part(451 a), the second main heat exchange part (451 b), and the third mainheat exchange part (451 c) are formed in this order from the bottom tothe top. In the lower heat exchange region (452), the first auxiliaryheat exchange part (452 a), the second auxiliary heat exchange part (452b), and the third auxiliary heat exchange part (452 c) are formed inthis order from the bottom to the top. As in the foregoing, in theoutdoor heat exchanger (40) of the present embodiment, the upper heatexchange region (451) and the lower heat exchange region (452) are eachdivided into the plurality of heat exchange parts (451 a-451 c, 452a-452 c), the number of which is the same between the upper heatexchange region (451) and the lower heat exchange region (452).Referring to FIG. 18, the main heat exchange part (451 a-451 c) includeseleven flat tube (53), and the auxiliary heat exchange part (452 a-452c) includes three flat tubes (58). Note that the number of heat exchangeparts (451 a-451 c, 452 a-452 c) formed in the heat exchange region(451, 452) may be two or may be equal to or greater than four.

In the present embodiment, the width of the flat tube (58) provided inthe auxiliary heat exchange part (452 a-452 c) is, as in the firstembodiment, greater than that of the flat tube (53) provided in the mainheat exchange part (451 a-451 c). Moreover, the number of flow paths perflat tube (58) provided in the auxiliary heat exchange part (452 a-452c) is greater than the number of flow paths per flat tube (53) providedin the main heat exchange part (451 a-451 c).

Internal spaces of the first header collecting pipe (460) and the secondheader collecting pipe (470) are each horizontally divided by aplurality of partition plates (439).

Specifically, the internal space of the first header collecting pipe(460) is divided into an upper space (461) corresponding to the upperheat exchange region (451) and a lower space (462) corresponding to thelower heat exchange region (452). The upper space (461) is a singlespace corresponding to all of the main heat exchange parts (451 a-451c). That is, the upper space (461) communicates with all of the flattubes (53) of the main heat exchange parts (451 a-451 c). The lowerspace (462) is, by the partition plates (439), further horizontallydivided into communication spaces (462 a-462 c) corresponding to theauxiliary heat exchange parts (452 a-452 c) such that the number (i.e.,three) of the communication spaces (462 a-462 c) is the same as that ofthe auxiliary heat exchange parts (452 a-452 c).

That is, in the lower space (462), the first communication space (462 a)communicating with the flat tubes (58) of the first auxiliary heatexchange part (452 a), the second communication space (462 b)communicating with the flat tubes (58) of the second auxiliary heatexchange part (452 b), and the third communication space (462 c)communicating with the flat tubes (58) of the third auxiliary heatexchange part (452 c) are formed.

The internal space of the second header collecting pipe (470) ishorizontally divided into five communication spaces (471 a-471 c).Specifically, the internal space of the second header collecting pipe(470) is divided into the four communication spaces (471 a, 471 b, 471d, 471 e) corresponding to the main heat exchange parts (451 b, 451 c)and the auxiliary heat exchange parts (452 a, 452 b) other than thefirst main heat exchange part (451 a) positioned lowermost in the upperheat exchange region (451) and the third auxiliary heat exchange part(452 c) positioned uppermost in the lower heat exchange region (452),and into the single communication space (471 c) corresponding to both ofthe first main heat exchange part (451 a) and the third auxiliary heatexchange part (452 c). That is, in the internal space of the secondheader collecting pipe (470), the first communication space (471 a)communicating with the flat tubes (58) of the first auxiliary heatexchange part (452 a), the second communication space (471 b)communicating with the flat tubes (58) of the second auxiliary heatexchange part (452 b), the third communication space (471 c)communicating with the flat tubes (53, 58) of both of the thirdauxiliary heat exchange part (452 c) and the first main heat exchangepart (451 a), the fourth communication space (471 d) communicating withthe flat tubes (53) of the second main heat exchange part (451 b), andthe fifth communication space (471 e) communicating with the flat tubes(53) of the third main heat exchange part (451 c) arc formed.

In the second header collecting pipe (470), the fourth communicationspace (471 d) and the fifth communication space (471 e) are pairedrespectively with the first communication space (471 a) and the secondcommunication space (471 b). Specifically, the first communication space(471 a) and the fourth communication space (471 d) are paired together,and the second communication space (471 b) and the fifth communicationspace (471 e) are paired together. Moreover, in the second headercollecting pipe (470), a first communication pipe (472) connectingbetween the first communication space (471 a) and the fourthcommunication space (471 d) and a second communication pipe (473)connecting between the second communication space (471 b) and the fifthcommunication space (471 e) are provided. That is, in the outdoor heatexchanger (40) of the present embodiment, the first main heat exchangepart (451 a) and the third auxiliary heat exchange part (452 c) arepaired together, the second main heat exchange part (451 b) and thefirst auxiliary heat exchange part (452 a) are paired together, and thethird main heat exchange part (451 c) and the second auxiliary heatexchange part (452 b) are paired together. Note that the number of pairsof the heat exchange parts (451 a-451 e, 452 a-452 c) formed in theoutdoor heat exchanger (40) is suitably set depending on the height ofthe outdoor heat exchanger (40) such that the total height of the mainheat exchange part (451 a-451 c) and the auxiliary heat exchange part(452 a-452 c) which are to be paired together is equal to or lower thanabout 350 mm (preferably about 300-350 mm)

As in the foregoing, in the internal space of the second headercollecting pipe (470), the communication spaces (471 c, 471 d, 471 e)corresponding to the main heat exchange parts (451 a-451 c) of the upperheat exchange region (451) are formed such that the number thereof(e.g., three) is the same as that of the main heat exchange parts (451a-451 c). Moreover, the communication spaces (471 a, 471 b, 471 c)corresponding to the auxiliary heat exchange parts (452 a-452 c) of thelower heat exchange region (452) are formed such that the number thereof(e.g., three) is the same as that of the auxiliary heat exchange parts(452 a-452 c). Further, the communication spaces (471 c, 471 d, 471 e)corresponding to the upper heat exchange region (451) and thecommunication spaces (471 a, 471 b, 471 c) corresponding to the lowerheat exchange region (452) communicate with each other.

Referring to FIG. 17, in the outdoor heat exchanger (40), a liquidconnection member (480) and a gas connection member (485) are provided.The liquid connection member (480) and the gas connection member (485)are attached to the first header collecting pipe (460).

The liquid connection member (480) includes a single distributor (481)and three thin pipes (482 a-482 c). A pipe connecting between theoutdoor heat exchanger (40) and an expansion valve (33) is connected toa lower end part of the distributor (481). The thin pipe (482 a-482 c)is, at one end thereof, connected to an upper end part of thedistributor (481). In the distributor (481), the pipe connected to thelower end part and the thin pipes (482 a-482 c) communicate with eachother. The thin pipe (482 a-482 c) is, at the other end thereof,connected to the lower space (462) of the first header collecting pipe(460), and communicates with a corresponding one of the communicationspaces (462 a-462 c).

Referring to FIG. 18, the thin pipe (482 a-482 c) opens at part of acorresponding one of the communication spaces (462 a-462 c) close to alower end thereof. That is, the first thin pipe (482 a) opens at part ofthe first communication space (462 a) close to the lower end thereof,the second thin pipe (482 b) opens at part of the second communicationspace (462 b) close to the lower end thereof, and the third thin pipe(482 c) opens at part of the third communication space (462 c) close tothe lower end thereof. Note that the length of the thin pipe (482 a-482c) is independently set such that the difference in flow rate ofrefrigerant flowing into the auxiliary heat exchange parts (452 a-452 c)is reduced as much as possible.

The gas connection member (485) is formed of a single pipe having arelatively-large diameter. The gas connection member (485) is, at oneend thereof, connected to a pipe connecting between the outdoor heatexchanger (40) and a third port of a four-way valve (34).

The gas connection member (485) opens, at the other end thereof, part ofthe upper space (461) close to an upper end thereof in the first headercollecting pipe (460).

According to the foregoing configuration, in the outdoor heat exchanger(40) of the present embodiment, refrigerant flows in a directionindicated by arrows illustrated in FIG. 17 in an air-cooling operation.In an air-heating operation, refrigerant flows in a direction oppositeto the direction indicated by the arrows illustrated in FIG. 17.

Fourth Embodiment of the Invention

An outdoor heat exchanger of a fourth embodiment of the presentdisclosure will be described. FIG. 19 is a front view illustrating aschematic configuration of the outdoor heat exchanger (40) of the fourthembodiment. Moreover, FIG. 20 is a partial cross-sectional viewillustrating a front side of the outdoor heat exchanger (40) of thefourth embodiment.

Referring to FIG. 19, flat tubes (53, 58) of the outdoor heat exchanger(40) are, as in the third embodiment, horizontally divided for an upperheat exchange region (451) and a lower heat exchange region (452). Theupper heat exchange region (451) is divided into three main heatexchange parts (451 a-451 c) arranged in the vertical direction, and thelower heat exchange region (452) is formed of a single auxiliary heatexchange part (452 a). That is, in the upper heat exchange region (451),the first main heat exchange part (451 a), the second main heat exchangepart (451 b), and the third main heat exchange part (451 c) are formedin this order from the bottom to the top. Referring to FIG. 20, the mainheat exchange part (451 a-451 c) includes eleven flat tubes (53), andthe auxiliary heat exchange part (452 a) includes nine flat tubes (58).Note that the number of main heat exchange parts (451 a-451 c) formed inthe upper heat exchange region (451) may be two or may be equal to orgreater than four.

Internal spaces of a first header collecting pipe (460) and a secondheader collecting pipe (470) are each horizontally divided by partitionplates (439).

In the present embodiment, the width of the flat tube (58) provided inthe auxiliary heat exchange part (452 a) is, as in the first embodiment,greater than that of the flat tube (53) provided in the main heatexchange part (451 a-451 c). Moreover, the number of flow paths per flattube (58) provided in the auxiliary heat exchange part (452 a) isgreater than the number of flow paths per flat tube (53) provided in themain heat exchange part (451 a-451 c).

Specifically, the internal space of the first header collecting pipe(460) is divided into an upper space (461) corresponding to the upperheat exchange region (451), and a lower space (462) (communication space(462 a)) corresponding to the lower heat exchange region (452). Theupper space (461) is a single space corresponding to all of the mainheat exchange parts (451 a-451 c). That is, the upper space (461)communicates with all of the flat tubes (53) of the main heat exchangeparts (451 a-451 c). The lower space (462) (communication space (462 a))is a single space corresponding to the single auxiliary heat exchangepart (452 a), and communicates with the flat tubes (58) of the auxiliaryheat exchange part (452 a).

The internal space of the second header collecting pipe (470) ishorizontally divided into four communication spaces (471 a-471 d).Specifically, the internal space of the second header collecting pipe(470) is divided into three communication spaces (471 b, 471 c, 471 d)corresponding respectively to the main heat exchange parts (451 a-451 c)of the upper heat exchange region (451), and a single communicationspace (471 a) corresponding to the auxiliary heat exchange part (452 a)of the lower heat exchange region (452). That is, in the internal spaceof the second header collecting pipe (470), the first communicationspace (471 a) communicating with the flat tubes (58) of the auxiliaryheat exchange part (452 a), the second communication space (471 b)communicating with the flat tubes (53) of the first main heat exchangepart (451 a), the third communication space (471 c) communicating withthe flat tubes (53) of the second main heat exchange part (451 b), andthe fourth communication space (471 d) communicating with the flat tubes(53) of the third main heat exchange part (451 c) are formed.

In the second header collecting pipe (470), a communication member (475)is provided. The communication member (475) includes a singledistributor (476), a single main pipe (477), and three thin pipes (478a-478 c). The main pipe (477) is, at one end thereof, connected to alower end part of the distributor (476), and is, at the other endthereof, connected to the first communication space (471 a) of thesecond header collecting pipe (470). The thin pipe (478 a-478 c) is, atone end thereof, connected to an upper end part of the distributor(476). In the distributor (476), the main pipe (477) and the thin pipes(478 a-478 c) communicate with each other. The thin pipe (478 a-478 c)communicates, at the other end thereof, with a corresponding one of thesecond to fourth communication spaces (471 b-471 d) of the second headercollecting pipe (470).

Referring to FIG. 20, the thin pipe (478 a-478 c) opens at part of acorresponding one of the second to fourth communication spaces (471b-471 d) close to a lower end thereof. That is, the thin pipe (478 a)opens at part of the second communication space (471 b) close to thelower end thereof, the thin pipe (478 b) opens at part of the thirdcommunication space (471 c) close to the lower end thereof, and the thinpipe (478 c) opens at part of the fourth communication space (471 d)close to the lower end thereof. Note that the length of the thin pipe(478 a-478 c) is independently set such that the difference in flow rateof refrigerant flowing into the main heat exchange parts (451 a-451 c)is reduced as much as possible. As described above, the communicationmember (475) of the second header collecting pipe (470) is connected soas to branch from the communication space (471 a) into the second tofourth communication spaces (471 b-471 d) corresponding respectively tothe main heat exchange parts (451 a-451 c). That is, in the secondheader collecting pipe (470), the communication space (471 a)corresponding to the lower heat exchange region (452) and thecommunication space (471 b-471 d) corresponding to the upper heatexchange region (451) communicate with each other.

Referring to FIG. 19, in the outdoor heat exchanger (40), a liquidconnection member (486) and a gas connection member (485) are provided.The liquid connection member (486) and the gas connection member (485)are attached to the first header collecting pipe (460). The liquidconnection member (486) is formed of a single pipe having arelatively-large diameter. A pipe connecting between the outdoor heatexchanger (40) and an expansion valve (33) is connected to one end ofthe liquid connection member (486). The liquid connection member (486)opens, at the other end thereof; at part of the lower space (462)(communication space (462 a)) close to a lower end thereof in the firstheader collecting pipe (460). The gas connection member (485) is formedof a single pipe having a relatively-large diameter. A pipe connectingbetween the outdoor heat exchanger (40) and a third port of a four-wayvalve (34) is connected to one end of the gas connection member (485).The gas connection member (485) opens, at the other end thereof, at partof the upper space (461) close to an upper end thereof in the firstheader collecting pipe (460).

According to the foregoing configuration, in the outdoor heat exchanger(40) of the present embodiment, refrigerant flows in a directionindicated by arrows illustrated in FIG. 19 in an air-cooling operation.In an air-heating operation, refrigerant flows in a direction oppositeto the direction indicated by the arrows illustrated in FIG. 19.

Fifth Embodiment of the Invention

A fifth embodiment of the present disclosure will be described. Thepresent embodiment is configured in such a manner that the configurationof the second header collecting pipe (470) of the outdoor heat exchanger(40) of the third embodiment is changed. The other configuration issimilar to that of the third embodiment. In the present embodiment, onlya configuration of a second header collecting pipe (470) of an outdoorheat exchanger (40) will be described with reference to FIGS. 21 and 22.

FIG. 21 is a front view illustrating the schematic configuration of theoutdoor heat exchanger (40) of the fifth embodiment. Moreover, FIG. 22is a partial cross-sectional view illustrating a front side of theoutdoor heat exchanger (40) of the fifth embodiment. Referring to FIG.22, an internal space of the second header collecting pipe (470) of theoutdoor heat exchanger (40) is vertically divided into threecommunication spaces (471 a-471 c) by two partition plates (439).Specifically, in the internal space of the second header collecting pipe(470), the first communication space (471 a), the second communicationspace (471 b), and the third communication space (471 c) are formed inthis order from the right as viewed in FIG. 22. The first communicationspace (471 a) communicates with flat tubes (53) of a third main heatexchange part (451 c) and flat tubes (58) of a first auxiliary heatexchange part (452 a). The second communication space (471 b)communicates with flat tubes (53) of a second main heat exchange part(451 b) and flat tubes (58) of a second auxiliary heat exchange part(452 b). The third communication space (471 c) communicates with flattubes (53) of a first main heat exchange part (451 a) and flat tubes(58) of a third auxiliary heat exchange part (452 c). In the outdoorheat exchanger (40), the third main heat exchange part (451 c) and thefirst auxiliary heat exchange part (452 a) are paired together, thesecond main heat exchange part (451 b) and the second auxiliary heatexchange part (452 b) are paired together, and the first main heatexchange part (451 a) and the third auxiliary heat exchange part (452 c)are paired together.

That is, in the second header collecting pipe (470) of the outdoor heatexchanger (40) of the present embodiment, the main heat exchange part(451 a-451 c) in an upper heat exchange region (451) is paired with acorresponding one of the auxiliary heat exchange parts (452 a-452 c) ina lower heat exchange region (452). The communication space (471 a-471c) for a corresponding one of the pairs of heat exchange parts (451a-451 c, 452 a-452 c) is formed such that the number (e.g., three) ofcommunication spaces (471 a-471 c) is the same as the number of pairs.As described above, in the second header collecting pipe (470), the flattubes (53, 58) of the pair of main heat exchange part (451 a-451 c) andauxiliary heat exchange part (452 a-452 c) directly communicate witheach other in the internal space of the second header collecting pipe(470).

In the present embodiment, the width of the flat tube (58) provided inthe auxiliary heat exchange part (452 a-452 c) is, as in the firstembodiment, greater than that of the flat tube (53) provided in the mainheat exchange part (451 a-451 c). Moreover, the number of flow paths perflat tube (58) provided in the auxiliary heat exchange part (452 a-452c) is greater than the number of flow paths per flat tube (53) providedin the main heat exchange part (451 a-451 c).

According to the foregoing configuration, in the outdoor heat exchanger(40) of the present embodiment, refrigerant flows in a directionindicated by arrows illustrated in FIG. 21 in an air-cooling operation.In an air-heating operation, refrigerant flows in a direction oppositeto the direction indicated by the arrows illustrated in FIG. 21.

Sixth Embodiment of the Invention

A sixth embodiment of the present disclosure will be described. Thepresent embodiment is configured in such a manner that the configurationof the outdoor heat exchanger (40) of the third embodiment is changed.Differences in the outdoor heat exchanger (40) between the presentembodiment and the third embodiment will be described with reference toFIGS. 23 and 24.

An internal space of a second header collecting pipe (470) of thepresent embodiment is, as in the third embodiment, horizontally dividedinto five communication spaces (471 a-471 e). In the second headercollecting pipe (470) of the present embodiment, the first communicationspace (471 a) and the fifth communication space (471 e) are pairedtogether, and the second communication space (471 b) and the fourthcommunication space (471 d) are paired together. Moreover, in the secondheader collecting pipe (470), a first communication pipe (472)connecting between the second communication space (471 b) and the fourthcommunication space (471 d) and a second communication pipe (473)connecting between the first communication space (471 a) and the fifthcommunication space (471 e) are provided. That is, in the outdoor heatexchanger (40) of the present embodiment, a first main heat exchangepart (451 a) and a third auxiliary heat exchange part (452 c) are pairedtogether, a second main heat exchange part (451 b) and a secondauxiliary heat exchange part (452 b) are paired together, and a thirdmain heat exchange part (451 c) and a first auxiliary heat exchange part(452 a) are paired together.

In the outdoor heat exchanger (40) of the present embodiment, aconnection position of a gas connection member (485) in a first headercollecting pipe (460) is changed. Specifically, the gas connectionmember (485) opens at a middle part of an upper space (461) (i.e., atthe middle of the upper space (461) in the vertical direction) in thefirst header collecting pipe (460). Further, referring to FIG. 24, inthe outdoor heat exchanger (40) of the present embodiment, the innerdiameter B1 of the first header collecting pipe (460) is greater thanthe inner diameter B2 of the second header collecting pipe (470). Such aconfiguration allows gas refrigerant flowing into the upper space (461)of the first header collecting pipe (460) through the gas connectionmember (485) to be equally distributed into the three main heat exchangeparts (451 a-451 c).

In the outdoor heat exchanger (40) of the present embodiment, the innerdiameters of the header collecting pipes (460, 470) may be equal to eachother, and the gas connection member (485) may open at part of the upperspace (461) close to an upper end thereof in the first header collectingpipe (460).

Seventh Embodiment of the Invention

FIG. 25 is a partial cross-sectional view of an outdoor heat exchanger(40) of a seventh embodiment. In the present embodiment, the width of aflat tube (53) of a main heat exchange part (50) and the width of a flattube (58) of an auxiliary heat exchange part (55) are equal to eachother. Moreover, as in the foregoing embodiments, the number of flattubes (58) of the auxiliary heat exchange part (55) is less than thenumber of flat tubes (53) of the main heat exchange part (50). Further,the total cross-sectional area of refrigerant flow paths (49) per flattube (58) provided in the auxiliary heat exchange part (55) is greaterthan the total cross-sectional area of refrigerant flow paths (49) perflat tube (53) provided in the main heat exchange part (50). Althoughnot shown in FIG. 25, the foregoing bare pipe (smooth inner pipe asillustrated in FIG. 7B) is, in the present embodiment, employed as theflat tube (53) of the main heat exchange part (50), and each of therefrigerant flow paths (49) has a circular cross section. On the otherhand, in the flat tube (58) of the auxiliary heat exchange part (55), aplurality of grooves are formed in each of the refrigerant flow paths(49) (see FIG. 7A). In such a configuration, the flow velocity ofrefrigerant in the auxiliary heat exchange part (55) can be lowered.Thus, in the present embodiment, a pressure loss in the auxiliary heatexchange part (55) can be also reduced.

Eighth Embodiment of the Invention

In an outdoor heat exchanger (40) of an eighth embodiment, the width ofa flat tube (53) of a main heat exchange part (50) and the width of aflat tube (58) of an auxiliary heat exchange part (55) are equal to eachother. Moreover, the number of flat tubes (58) of the auxiliary heatexchange part (55) is less than the number of flat tubes (53) of themain heat exchange part (50).

Further, the total cross-sectional area of refrigerant flow paths (49)per flat tube (58) provided in the auxiliary heat exchange part (55) isgreater than the total cross-sectional area of refrigerant flow paths(49) per flat tube (53) provided in the main heat exchange part (50).Specifically, the number of refrigerant flow paths (49) in the flat tube(53) of the main heat exchange part (50) is less than the number ofrefrigerant flow paths (49) in the flat tube (58) of the auxiliary heatexchange part (55). In such a configuration, the flow velocity ofrefrigerant in the auxiliary heat exchange part (55) can be lowered.Thus, in the present embodiment, a pressure loss in the auxiliary heatexchange part (55) can be also reduced. Note that each of therefrigerant flow paths (49) of the heat transfer pipe (53, 58) in themain heat exchange part (50) or the auxiliary heat exchange part (55)may be provided with or without grooves (see FIGS. 7A and 7B).

Note that, in each of the outdoor heat exchangers (40) of the second toeighth embodiments, various fins such as the fins (54, 59, 235, 236)described in the first embodiment and the variations thereof may beemployed.

INDUSTRIAL APPLICABILITY

The present disclosure is useful as the heat exchanger including theflat tubes and the fins and configured to exchange heat between fluidflowing through the flat tube and air and as the air conditioner.

DESCRIPTION OF REFERENCE CHARACTERS

-   10 Air Conditioner-   40 Outdoor Heat Exchanger (Heat Exchanger)-   49 Refrigerant Flow Path (Flow Path)-   50 Main Heat Exchange Part-   51, 56 First Header Collecting Pipe-   52, 57 Second Header Collecting Pipe-   53 Flat tube-   54, 59 Fin-   55 Auxiliary Heat Exchange Part-   58 Flat tube

1-6. (canceled)
 7. A heat exchanger including a plurality of flat tubesarranged in a vertical direction and each formed with a plurality offlow paths of fluid, and a plurality of fins configured to divide partbetween adjacent ones of the flat tubes into a plurality of air passagesthrough each of which air flows, comprising: a first header collectingpipe; and a second header collecting pipe, wherein each flat tube is, atone end thereof, connected to the first header collecting pipe, and is,at the other end thereof, connected to the second header collectingpipe, some of the flat tubes form a main heat exchange part, and theother flat tubes form an auxiliary heat exchange part, the flat tubesforming the auxiliary heat exchange part are fewer than the flat tubesforming the main heat exchange part, a total cross-sectional area of theflow paths per flat tube in the auxiliary heat exchange part is greaterthan a total cross-sectional area of the flow paths per flat tube in themain heat exchange part, and if the heat exchanger serves as acondenser, refrigerant is condensed in the main heat exchange part, andthe refrigerant is sub-cooled in the auxiliary heat exchange part. 8.The heat exchanger of claim 7, wherein a width (W2) of each flat tube ofthe auxiliary heat exchange part is greater than a width (W1) of eachflat tube of the main heat exchange part, and the flow paths per flattube in the auxiliary heat exchange part is more than the flow paths perflat tube in the main heat exchange part.
 9. The heat exchanger of claim7, wherein each flow path is formed with a plurality of grooves in acorresponding one of the flat tubes of the main heat exchange part, andeach flat tube of the auxiliary heat exchange part is a bare pipe. 10.The heat exchanger of claim 7, wherein each fin is formed in such aplate shape that a plurality of cut parts into each of which acorresponding one of the flat tubes is inserted are provided, the finsare arranged at predetermined intervals in an extension direction of theflat tubes, each flat tube is sandwiched between peripheral edge partsof a corresponding one of the cut parts of the fins, and in each fin,part between adjacent ones of the cut parts arranged in the verticaldirection forms a heat transfer part.
 11. The heat exchanger of claim10, wherein an end of each flat tube in a width direction thereof isaligned with an end of a corresponding one of the cut parts on an openside thereof.
 12. An air conditioner, comprising: a refrigerant circuitprovided with the heat exchanger of claim 7, wherein refrigerantcirculates to perform a refrigeration cycle in the refrigerant circuit.13. The heat exchanger of claim 8, wherein each flow path is formed witha plurality of grooves in a corresponding one of the flat tubes of themain heat exchange part, and each flat tube of the auxiliary heatexchange part is a bare pipe.
 14. The heat exchanger of claim 8, whereineach fin is formed in such a plate shape that a plurality of cut partsinto each of which a corresponding one of the flat tubes is inserted areprovided, the fins are arranged at predetermined intervals in anextension direction of the flat tubes, each flat tube is sandwichedbetween peripheral edge parts of a corresponding one of the cut parts ofthe fins, and in each fin, part between adjacent ones of the cut partsarranged in the vertical direction forms a heat transfer part.
 15. Theheat exchanger of claim 9, wherein each fin is formed in such a plateshape that a plurality of cut parts into each of which a correspondingone of the flat tubes is inserted are provided, the fins are arranged atpredetermined intervals in an extension direction of the flat tubes,each flat tube is sandwiched between peripheral edge parts of acorresponding one of the cut parts of the fins, and in each fin, partbetween adjacent ones of the cut parts arranged in the verticaldirection forms a heat transfer part.
 16. The heat exchanger of claim13, wherein each fin is formed in such a plate shape that a plurality ofcut parts into each of which a corresponding one of the flat tubes isinserted are provided, the fins are arranged at predetermined intervalsin an extension direction of the flat tubes, each flat tube issandwiched between peripheral edge parts of a corresponding one of thecut parts of the fins, and in each fin, part between adjacent ones ofthe cut parts arranged in the vertical direction forms a heat transferpart.
 17. The heat exchanger of claim 14, wherein an end of each flattube in a width direction thereof is aligned with an end of acorresponding one of the cut parts on an open side thereof.
 18. The heatexchanger of claim 15, wherein an end of each flat tube in a widthdirection thereof is aligned with an end of a corresponding one of thecut parts on an open side thereof.
 19. The heat exchanger of claim 16,wherein an end of each flat tube in a width direction thereof is alignedwith an end of a corresponding one of the cut parts on an open sidethereof.
 20. An air conditioner, comprising: a refrigerant circuitprovided with the heat exchanger of claim 8, wherein refrigerantcirculates to perform a refrigeration cycle in the refrigerant circuit.21. An air conditioner, comprising: a refrigerant circuit provided withthe heat exchanger of claim 9, wherein refrigerant circulates to performa refrigeration cycle in the refrigerant circuit.
 22. An airconditioner, comprising: a refrigerant circuit provided with the heatexchanger of claim 10, wherein refrigerant circulates to perform arefrigeration cycle in the refrigerant circuit.
 23. An air conditioner,comprising: a refrigerant circuit provided with the heat exchanger ofclaim 11, wherein refrigerant circulates to perform a refrigerationcycle in the refrigerant circuit.
 24. An air conditioner, comprising: arefrigerant circuit provided with the heat exchanger of claim 13,wherein refrigerant circulates to perform a refrigeration cycle in therefrigerant circuit.
 25. An air conditioner, comprising: a refrigerantcircuit provided with the heat exchanger of claim 14, whereinrefrigerant circulates to perform a refrigeration cycle in therefrigerant circuit.
 26. An air conditioner, comprising: a refrigerantcircuit provided with the heat exchanger of claim 15, whereinrefrigerant circulates to perform a refrigeration cycle in therefrigerant circuit.